Method of and apparatus for the manufacture of diapositives for the projection of light pictures in natural colors



. H. DIERNHOFER METHOD OF AND APPARATUS FOR THE MANUFACTURE OF DIAPOSITIVES FOR THE PROJECTION OF LIGHT PICTURES IN NATURAL COLORS Filed June 15. 1922 2 Sheets-Sheet 1 Etta rney.

Oct. 27, 1925. 1,559,316

H. DIERNHOFER METHOD OF AND APPARATUS FOR THE MANUFACTURE OF DIAPOSITIVES FOR THE PROJECTION OF LIGHT PICTURES IN NATURAL COLORS Filed June 15 1922 2 Sheets-Shoot 2 FIELS- 3y! m y. fittornty,

Patented Oct. 27, 1925.

UNITED STATES PATENT OFFICE.

HERMANN DIERNHOFER, OF ZITTAU, SAXONY, GERMANY.

METHOD OF AND AJPPARATUS FOR THE MANUFACTURE OF DIAPOSITIVES FOR THE PROJECTION OF LIGHT PICTURES IN NATURAL COLORS.

Application filed June 15, 1922. Serial No. 568,652.

To all whom it may concern:

Be it known that I, HERMANN DIERN- HOFER, a citizen of the German Republic, and a resident of Zittau, Saxony, Germany, have invented a new and useful Improved Method of and Apparatus for the Manufacture of Diapositives for the Projection of Light Pictures in Natural Colors, of which the following is a specification.

1 This invention relates in its first part to a novel method for the manufacture of diapositives intended for projecting light pictures or illuminated pictures in natural colors, and in its second part to an apparatus by which that method may be carried into effect. The advantage obtained by this novel method resides in this that it is no more necessary, as heretofore, to employ for the projection three separated part-diapositives which must be made exactlv fitting to one another, but one diapositive containing the former three part-diapositives is sufiicient, the projected pictures of different colors fitting mathematically exactly to one another without a preceding adjustment.

Hitherto it was necessary to make the three part-diapositives fit one to the other or others either at the projection procedure itself or with aid of suitable mechanical means whereby, however, the performance was considerably disturbed and a loss of time caused; furthermore, also the aesthetic, impression-of the performance is disagreeably impaired. Making the part diapositives fit to one another was to be effected either with aid of a specially devised microscope or in the projection apparatus itself with aid of a metal frame provided with adjusting means. All these contrivances entail the extraordinarily serious drawback that for each individual three color picture a very expensive metal frame with precision adjusting screws must be on hand so that even if the store of diapositives is but small very great costs are incurred, in consequence of which only a comparatively small number of such frames can be kept on stock.

Another consequence is that the dia-positives adjusted with such an expenditure of time and pains must always-again be exchanged which causes an extraordinarily great loss of time, work and costs.

All these drawbacks are effectively overcome by the present invention in which the adjustment of the diapositives is entirely dispensed with. Instead thereof the multicolor projection apparatus is provided with a device by means of which the negatives that form the bases for the projection-diapositives are made to cover one another on the projection screen, after which they are secured to a common base plate immovably with respect to each other. When then a transparent copy is made from the thus combined negatives in an ordinary copying frame they deliver a diapositive which produces in its turn, with aid of a suitable projection apparatus, an excellent multi-color picture in which all bordering lines exactly coincide each other.

My improved process is carried into practice by means of the improved apparatus illustrated, by way of example, in the accompanying drawing in which Fig. l is a plan of one form of construction of such an apparatus. Fig. 2 is a section in line II of Fig. 1. Fig. 3 is an illustration similar to the upper half of Fig. 1 and shows another form of construction. Fig. 4 is an illustration similar to Fig. 3 and shows a third form of construction. Fig. 5 is a section in line IIII of Fig. 4.

Referring to Figs. 1 and 2, a is a frame, preferably of metal, having in its bottom an oblong window 6 covered with a glass plate 0 which rests immovably in a cavity d of the frame. The negatives serving to manufacture the part-diapositives (in the example shown in said figures the negatives e, f and g) are placed upon the glass plate 0 in such a manner that first the negative (2 is inimovably aflixed to the glass plate either by pasting it on, or by mechanical means. Then also the second (f) and after it the third (g) negative are affixed to the glass plate upon which each is displaced until its contours, or bordering lines coincide exactly with the negative e.

Displacing the negatives f and g is etfected by the following means: Above and below a ledge vll are cavities i 2', each of which contains three adjusting spindles 7, k, Z having a very fine thread at their ends and being self-locking; the threaded end portions are supported in correspondingly threaded-bearings m. The middle spindle is with its thread serves for displacing the appertaining negative in lateral direction.

To transmit the motion, a slide 0' is displaceable in guides n, n and is pulled against the threaded end of k by a spring 2. To the other end of the slide is afiixed a transferred piece 9, the ends of which are bent upwards and carry an axle r. One of these ends has merely a hole for the reception of the respective end of the axle 1'; the other, however, has a horizontal slot 8 which re ceives the other end of that axle. The axle 7' has secured to it a. frame t provided with two pressure springs having attached to their lower sides cheeks a bearing a ainst the longitudinal edges of the negatlve f, or g respectively. A spring 4: pulls the frame 15 constantly to the left and makes the upper end of the axle r bear against the threaded end of the spindle j. The lower end of the axle r bears against an angular member 20 secured to an obliquely arranged pin 3 guided in a stationary guide as. The other end of the pin bears against an angular member a which is connected with the spindle Z by feather and groove and is, therefore, displaced in the direction of the spindle Z but not rotated by it. Owing to the obliquity of the parts y and m the member w is not only longitudinally displaced, but transversely also, so that the axle 1 and the frame It, by reason of the pull of the spring '0, partake in this latter motion, whereby the negative 6 is adjusted also in this direction. It is, thus, obviously possible to adjustthe negative f exactly with respect to the negative e, and the same is true of the negative ,7 (with respect to the negative e) because the arrangement and combination of parts co-operating with the spindles provided for this negative is just the same as that provided for the negative f. This is true not only of the spindles k and Z, but of the spindle j, too. The object of this spindle is to displace in a turning manner the negative f, or g respectively, by pressing against the upper end of the axle 1' and displace it laterally in the slot 8 of one of the angular ends of the transverse piece That is the third means for adjusting t e negative f, or g respectively, so that it is made possible in a convenient and reliable manner to make glass plate 0 by sealing wax or the like, and

when this or an Tether fastening means has sufficiently har ened, the glass plates with spindles with threads but by levers.

its negatives is taken out of the frame and used 1n the usual way for making a transparent copy which now contains the partdiapositives necessary for multi-color pro jection and renders possible to produce on the screen the multi-color picture without any further adjustment, the screen being of course, as far distant from the apparatus as when the above-described adjustments were effected.

The second form of construction illustrated in Fig. 3 differs from Figs. 1 and 2 firstly by the omission of the coil springs p and 11 which, perhaps, may give rise to disturbances; secondly by the adjusting of the upper and the lower negative not by This arrangement and combination of parts is somewhat simpler than that first described and the reliability as to accuracy in adjusting the negatives is, perhaps still greater.

In Fig. 3 the axle 1' of each elastic framet (only one is shown, but there are two, as in Fig. 1) is turnable in its bearings, but not axially displaceable in the upwardly bent ends of the transverse member and this latter is not rigidly connected with the appertaining slide (such as 0, Figs. 1 and 2) butis movably connectedwith a slide 1 by means of a screw or the like 2. The slide 1 is longitudinally guided on the one .side by pins 3, 3 and on the other side by a bow-shaped spring 4, and is connected with a lever-like arm 5 fulcrumed at 6 by means of a rod 7. The slidel is guided also at its upper surface by an arm 8, the fastening screw of which serves at the same time to secure the bow-shaped spring 4 in place. Also the turnable traverse g is guided at its upper side by an arm 9 attached to the slide 1, this arm taking over a lateral lug of the traverse, as shown. Turning the traverse upon the slide is effected by a rod 12 connected at one end with it and at the other end with a lever-like arm 10 fulcrumed at 11 to the frame a.

The slide 1 is supported in its turn upon a T-shaped slide 13: the head of the T is guided on the side by the pins 15 and on the other side by a bow-shaped spring 14 somewhat alike the spring 14 at the side of the slide 1. The slide 13 is prevented from lifting by means of a flat member 16 taking over a lateral lug 17 of said slide. Adjusting the slide 13 with the parts it carries is effected by an arm 18* forming a projection of a lever 18 fulcrumed at 19 to the bottom of the cavity 2' and having at its inner end a slot 20' coupled with a pin 21 of the slide 13. Adjusting the negative proceeds. with this form of construction of the apparatus, in this way that the adjustment in vertical direction is effected by the lever 18 and in horizontal direction by the lever 5, whereas the angular lateral motions are effected by the lever 10. The arrangement of these levers is such that their movements correspond to that of the projected pictures, that is to say, if the picture is to be lifted, also the respective lever is lifted, and so on as regards the other directions.

In the form of construction illustrated in Figs. 4 and 5 the arrangement of the adjusting members is such that each adjustment is perfectly independent of the other ones so that the exactness of the adjustments is the greatest attainable. The slide 13 supports another slide 27 having a pin 32 engaging a slot 31 of the slide 13. The slide 27 is connected by a rod 7 with an angular lever or arm 5 fulcrumed at 6, as in Fig. 3. Also guiding the slide 13 is effected practically in the same manner as in Fig. 3, viz. by the pins 15, the lug 17, and the member 16. The slide 27 is elongated in forward direction beyond the plate 0 and has in this elongation arecess which is located opposite to the plate 0, or to the negative f or g respectively, and is so shaped that it is guided below the plate 0 with only two rods in corresponding slots of the rear and the front recess 5 of the frame (I.

There is, furthermore, a frame 40 having Near to the upper rear corner of the frame 40 is a lug 3 where a connecting rod 34 is hinged to this frame. The other 'end of said rod is connected with one end of a double-armed lever 36 fulcrumed at 35 to the slide 27, and the other arm of this lever is connected with a thrust bar 38 connected with a lever or arm Hulcrumed at 39.

Concerning the adjustment of the negatives in horizontal and in vertical direction the mannerof actuation and operation of the parts described with respect to Figs. 4-.

and 5 is practically the same as that described with regard to Fig. 3, but concerning the angular motion of the frame 40 with the negative therein contained there is that difference, that the negative in question is turned not around a point that hes outside the negative but just in its center. The

negative is adjusted firstapproximately by means of the lever 10 by slewing this latter downwards, provided, the rear edge of the negative is to be slewed downwards, the front edge however, upwards. The rod 38 taken along forward (to the right, as regards Fig. 4) during that motion and the lever 36 is turned on the'pivot 35 in clockwise direction, in consequence of which the rod is pulled downwards the frame 40 with the negative is turned in such a way that its rear (left hand) edge is turned downwards around the center of the negative f, or g respectively, because the guides 28 and 29 lie concentrically with respect to that center, or with respect to an axis extending tl'irough it. Only then the negative is adjusted also in vertical and in horizontal direction by the arms 5 and 18*, as already described. Finally, the ultimate adjustment by turning to one or the other side is effected again by the arm 10, the first rotary adjustment having been but approximate, as also already stated.

It is obvious that the adjustment around the center of the negative permits of effecting a very accurate coinciding of the negatives on the screen, the more, as the various adjustments are entirely independent from one another, none of them aflecting any of .the others in any way.

It is possible to substitute for the two guides 28 and 29 a middle ledge, for instance a horizontal one, in the frame 40 and to provide in this ledge the slewing pivot concentrically with the center of the picture, this pivot being then supported in a corresponding transverse ledge in the recess of the front elongation of the slide 27 opposite the picture. If it is possible to mark the centers on the pictures, or on the negatives respectively, or by corresponding line on their rims, the slewing pivot in question may be provided with a very fine central hole whereby the center of the picture may be indicated on the screen for the adjusting purpose. Thus, with such a transverse ledge just the center and a middle stripe of the rojected picture is covered, but at the sides of the ledge (above and below it in the case of a horizontal ledge, or lefthand and righthand in the case of a vertical ledge) remains sufficient portions of the picture to effect with their aid the exact adjustment.

It must be. said that with respect to Figs. 4 and 5 there is a certain, although extremely little, possibility that the lateral adjustment of the negatlve is affected by the vertical one, viz. b a re-action of the arm 5 upon the slide 2 In other words: the rod 7 instead of turning the arm 5 may displace uite a little the slide 27 relatively to the s ide 13, or the slide 27 may be moved simultaneously with the arm 5, if the resistance which the slides meet with on the slide 13 is less than that resistance which the selflocking arm or lever 5 meets with on the frame, viz. against slewing motion. Such a possibility, although, perhaps chiefly theoretical, may be entirely done away with by arranging the arm or lever 5 not upon the frame a, but upon a lower rear pro ection of the slide 13 as shown in Fig. 4?. In this case, when adjusting the position of height of the slide 13, also the slewing pivot of the arm or lever 5, as well as the rod 7, are moved upwards or downwards, as the case may be, without any slewing motion whatever, whereby even the slightest motion of the slide 27 relatively to the slide 13 is absolutely prevented.

With all forms of construction above described, the three part negatives are made to coincide on-the screen in such a manner that a threefold diapositive made with their aid throws upon the screen, without any further adjustment, but in proper distance from the screen, viz, the same as before when dealing with the negatives, the three partpictures in such a manner that the projected picture shows no other but coinciding lines, another presupposition being that the threefold diapositive plate is located in the same angle with respect to the three projective objectives as previously thereto the plate with respect to the negatives. Badly cut diapositive plates, as regards that angle (such plates happen to be made), are likely to produce projections in which the lines do not coincide inspite of the previous exact adjustment of the part-negatives, but appear to be displaced with respect to each other.

In order to quickly do away with such insuflicient coincidence of the lines it is necessary that after the shoving in of the three-v fold diapositive, if this does not stand parallel to the projection objectives, the par allellity is brought about by a rotary motion of the frame holding the diapositive. Such a motion may be effected by making the lower surface of the frame not fiat but arcuate. The necessary motion may then be effected by eccentrically acting levers or by a cog-wheel gearing.

A somewhat different means for slewing the total picture is illustrated in Fig. 1 Where the main frame a is slewable in a vertical plane and in the longitudinal direction of the plate 0 on a pivot 22 and is supported by an eccentric disk 23 located on the side bearing the adjusting screws j, 70, Z. The disk 23 may be rotated by means of a self-locking disk 24 having a screw with a milled head by means of which it may be turned'where-by the frame in question. is raised or lowered.

Such an adjusting device for the proper relative angular position of the parts concerned is attached, concerning the negatives, to their adjusting frame, and concerning the diapositive, to the projection frame of or for thesame.

The adjustment may, however, be effected, if desired or preferred, after the colored pictures, or the color plates (for red, blue, and

.be carried through also in this way that not the upper and the lower negative, but the corresponding two objectives are adjusted with respect to the middle objective in order to attain the exact coincidence of the three projection pictures for different distances of the projection screen from the projection apparatus.

Having now described my invention, what I claim as new anddesire to secure by Letters Patent of the United States is:

1. The method of manufacturing diapositives for the projection of illuminated pictures in'natural colors upon a screen or the like, which method consists in first adjusting the negatives of the part pictures necessary for the multicolor projection abreast each other while projecting them on the screen one upon the other and observing the projections in regard to coincidence, fastening the negatives in the adjusted position abreast each other and making a common diapositive from said adjusted part pictures, said common diapositive showing the part diapositives abreast each other.

2. An apparatus for the manufacture of diapositives for the projection of illuminated pictures in natural colors on a screen or the like, comprising, in combination, a ground plate supporting the stationary negative, frames for securing on said ground plate the negatives which are to be adjusted with respect to said stationary negative while the projections of said negatives on the screen are being observed in regard to coincidence, lon itudinally and transversely dis laceable bri ges supportin said frames, an means for adjusting sai bridges and frames with respect to the projected images of the stationary negative and of the negatives to be adjusted.

3. An' apparatus for the manufacture of diapositives for the projection of illuminated pictures in natural colors on a screen or the like, comprising, in combination, a ground plate supporting the stationary negative, frames for securing on said ground plate the negatives which, are to be adjusted with respect to said stationary negative while the projections of said negatives on- 4. An apparatus for the manufacture of diapositives for the projection of illuminated pictures in natural colors on a screen .or the like, comprising, in combination, a

ground plate supporting the stationary negative, frames for securing on said ground plate the negatives which are to be adjusted with respect to said stationary negative While the projections of said negatives 0n the screen are being observed in regard to coincidence, lon itudinally and transversely displaceable bri ges supportin said frames, manually operatable means for adjusting said frames and bridges in one direction, and resilient means for adjusting said bridges and frames in the other direction.

5. An apparatus for the manufacture of diapositives for the projection of illuminated pictures in natural colors on a screen or the like, comprising, in combination, a ground plate supporting the stationary negative, frames for securing on said ground plate the negatives which are to be adjusted with respect to said stationary negative while the projections of said negatives on the screen are being observed in regard to coincidence, longitudinally and transversely displaceable bridges supporting said frames, means for adjusting said bridges and frames with respect to the projected images of the stationary negative and of the negatives to be adjusted, projections provided on said frames and guides arranged concentrically to the center of the image on said bridges and adapted to co-operate with said projections.

6. An apparatus for the manufacture of diapositives for the projection of illuminated pictures in natural colors on a screen or the like, comprising, in combination, a ground plate supporting the stationary negative, frames for securing on said round plate the negatives which are to be a justed with respect to said stationary negative While the projections of said negatives on the screen are being observed in regard to coincidence, lon itudinally and transversely displaceable bridges supporting said frames, and means for turning said frames-on said bridges around the axis of projection, after thelatter is adjusted in such a manner as to coincide with the center of the image to be projected, said means for turning said frames being arranged on one of said bridges.

7. An apparatus for the manufacture of diapositives for the projection of illuminated pictures in natural colors on a screen or the like, comprising, in combination, a ground plate supporting the stationary negative, frames for securing on said'ground plate the negatives, which are to be adjusted with respect to said stationary negative while the projections of said negatives on the screen are being observed in regard to coincidence, longitudinally and transversely displaceable bridges, supporting said frames, and manually operatable levers for adjusting in vertical and lateral directions said bridges and frames, supporting the ncgatives to be adjusted.

8. An apparatus for the manufacture of diapositives for the projection of illumi-- nated pictures in natural colors on a screen or the like, comprising in combination, a ground plate supporting the stationary negative, rames for securing on said ground plate the negatives which are to be adjusted with respect to said stationary negative while the projections of said negatives are being observed in regard to coincidence, longitudinally and transversely displaceable bridges supporting said frames, and levers fulcrumed separately on one of the respective bridges and being adapted to turn said frames on the respective bridge.

9. An apparatus for the manufacture of diapositives for the projection of illuminated pictures in natural colors on a screen or the like, comprising, in combination, a ground plate supporting the stationary negative, frames for securing on said ground plate the negatives which are to be adjusted with respect to said stationary negative While the projections of said negatives on the screen are being observed in regard to coincidence, lon itudinally and transversely displaceable bri ges supporting said frames, and means for adjusting the ground plate and the negatives fixed and adjusted thereon in such a manner that the axes of said negatives lie in one plane with the axes of the objective.

' HERMANN DIERNHOFER. 

